1. Field of the Invention
The present invention relates to a structure for mounting a key top of a keyboard used in various input devices of personal computers, word processors, etc. Particularly, it is concerned with a keyboard key top mounting structure which is effective in improving the lever assembling work efficiency between lever support means attached to a key top and components mounted on a stationary member side such as a printed circuit board and which is suitable for a smooth operation of a lever.
2. Description of the Prior Art
FIG. 11 is a development view of a conventional key top mounting structure of a large key size.
According to the prior art illustrated in FIG. 11, lever support means 2-5 are attached to the back of a key top 1 of a large key size and a stem engaging projection 8 is formed on the same side. Among the lever support means 2-5, a set of the lever support means 2 and 3 are for engagement with end portions 6a and 6b of a lever 6, while a set of the lever support means 4 and 5 are for engagement with end portions 7a and 7b of another lever 7.
On the other hand, lever fitting portions 10-13 are attached to a stationary member 9 such as a printed circuit board or a panel and a push-button switch 14 is provided on the same side. Among the lever fitting portions 10-13, a set of the lever fitting portions 10 and 11 are for fitting therein of an intermediate portion of the lever 6, while a set of the lever fitting portions 12 and 13 are for fitting therein of an intermediate portion of the other lever 7. The push-button switch 14 is provided with a stem 15 having a fitting hole 16.
The stem engaging projection 8 formed on the key top 1 is fitted in the lever fitting hole 16 of the stem 15 in the course of engagement of the levers 6 and 7 with the lever fitting portions 10, 11 and 12, 13, respectively.
In the above conventional key top mounting structure, the levers 6 and 7 are freely pivotable using as fulcrums their end portions 6a, 6b and 7a, 7b engaged with the lever support means 2, 3 and 4, 5, respectively. Therefore, the levers 6 and 7 pivot when fitted in the lever fitting portions 10, 11 and 12, 13, respectively, and thus the lever assembling work efficiency is very bad.